I'm having trouble doing the reverse polymorphic association when I have an inherited class. Anyone know what's going on?
ruby-1.9.2-rc2 > Label.first
=> #<Label id: 1, owner_id: 1, owner_type: "Student", name: "Lorem", created_at: "2011-01-23 05:02:29", updated_at: "2011-01-23 05:02:29">
ruby-1.9.2-rc2 > Label.first.owner
=> #<Student id: 1, email: "alice1@example.com", ..., avatar_updated_at: nil>
ruby-1.9.2-rc2 > Label.first.owner.labels
=> []
class Student < User
has_many :labels, :as => :owner
class Label < ActiveRecord::Base
belongs_to :owner, :polymorphic => true
Note: just for good measure (not that this should be any different, but 开发者_开发知识库just in case...)
User.find(1).labels
=> []
Also
l = Label.find(4)
=> #<Label id: 4, owner_id: 2, owner_type: "Student", name: "sit", created_at: "2011-01-23 05:02:29", updated_at: "2011-01-23 05:02:29">
ruby-1.9.2-rc2 > l.owner_type = "User"
=> "User"
ruby-1.9.2-rc2 > l.save
=> true
ruby-1.9.2-rc2 > Student.find(2).labels
=> [#<Label id: 4, owner_id: 2, owner_type: "User", name: "sit", created_at: "2011-01-23 05:02:29", updated_at: "2011-01-23 07:13:37">]
Still not sure why it was failing (well, I can guess, given the Student/User dichotomy), but for future reference this hack works:
has_many :labels, :conditions => ["owner_type = ?", "Student"],
:foreign_key => "owner_id"
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